What should I learn to understand syntax like these as described in the images?

[love_electronic]

What shoud i learn to understand syntax like these as described in the images

Hi guys
I am learning the ARM processor programming.I am very much confused about pointers, structure and the things defined in the below images.


What are these highlighted lines? What these are called? How and from where i learn these things?

Thanks

 

[barry]

Re: What shoud i learn to understand syntax like these as described in the images

Those are called "pound defines". Basically, anywhere in your code you have the first element it will be replaced with the second element. This is often used to define constants or macros. You can find all the information you asked about in any C language reference.